iPhone connects and disconnects from Mac

Guys

I have been having this issue for months, maybe years! (actually I ignored it so much since it happens very rarely to be really useful to connect my iCloud-based devices to my Mac).

After having tried almost everything (flag in network settings for USB iPhone, killing that process.. CHANGIG CABLE! god, how many cables I did change!!), i just realised that the "true" answer is this one:

Your device should be "sufficiently charged". IF the battery is too low the usb port of your computer is not able to feed it as needed, and the connection is lost.

If you have a look at these posts, in fact, it would seem that the problem affects in particular laptops, more than iMac and so on..

So guys.. sad enough Apple did not allow us to "power up" that USB, but at least we have a solution!

p.s. in my case the problem was with iPhone 7Plus, iPhone XS Max, iPad Pro 9.7 with a 2016 topped up MacBook Pro (latest before Touch Bar)

cheers, and thanks to the repliers!

Ok I can also confirm that after doing ALL suggested fixes, the one that fixed it and allowed me to sync my photos was simply to have the phone charged up a lot (94% charge).

It sounds easy but its annoying to have to charge your phone at a wall socket, then sync photos as ideally I'd do them both simultaneously .

But hey, what do I know? I'm just a stupid iPhone & Mac customer who knows nothing........

I've been having this problem for some time. I've tried all of the solutions: ensuring my iPhone was more then 50% charged, resetting the network setting, tried different cords, etc. Nothing has worked. As of this week, I can no longer sync my iPhone via Wifi. The sync keeps hanging. What a drag this is.

Have you tried the activity monitor method? It’s quite tricky, but once you get the timing right it’s easy. Look for, and force end, the process called usbd one the phone is connected. It’s quite finniky as photos, iTunes and all sorts of other stuff pop up appear in the way of the activity monitor terminal but once it’s done it works.

Also on another note, your problem sounds a big deeper than the typical problem here.

Also try a higher charge. In the 90% range before plugging in.

Let me know.

Same problem and tried all the rubbish on this site - new Cables , Network settings changed , Time stamps etc - Is there no one in Apple with a Brain or even a suggestion on how to fix this before I go back to an Android and a Windows Laptop - bloody poor support

Essentially I reset network settings on my phone then "re trusted" the phone to my laptop, it works temporarily. I have since got a new phone which works so not sure if its a glitch with new software on older phones as my old phone was a 7 with an X its working fine.

Also check your registered apple devices as you can some times have too many and that can stop the "Trusted" function from working.

Good luck.

Have you tried with over 90% battery?

Yes its annoying and defeats the object of having your MacBook even having a USB port but still.

Would be interesting to know.

Would be more interesting if @Apple even cared to assist....

Hi Mélody,

I had the same problem and contacted Apple support by phone. Try this:

1. Turn off your MacBook Air

2. Press and hold "Shift+CTRL+ALT(option)+Power" (11 seconds) and release

3. Turn on your MacBook Air as normal

4. Log in

5. Connect your iPhone

This resets your USB ports. In my case, it was a software issue, not a problem with the ports, the cable or the phone itself.

I hope that helps.

Jack

You get no information about this on your iphone, but if you go into the Itunes app on your macbook while the iphone is connected with a cable, it will notify you about updating your iphone to the latest software before you can charge, i'm guessing this is a security thing.

This issue appears to often be related to the power on the phone. When it's on a very low charge, it doesn't connect properly. (However, it seems to continually cycle through trying to connect, flashing on and off. Which is not really very helpful to the device or toubleshooting.)

I'm not sure what the minimum charge it accepts is, but as long as your device is charged to 'out of the red', you should be okay.

I have a similar problem. iPhone 7 Plus, MacBook Pro (2015).

With same cable (or older cable from Anker) and Laptop, no problems with iPhone 6s and 6 Plus, only with 7 Plus (if it is not fully charged). Problem goes gradually away if iPhone 7 Plus is charged more than 70-90%.

However, with newer cables (both genuine apple and from Anker) I have no problems.

Have you maybe used an older cable from your previous iPhone?

Of course, YMMV.

NONE of these solutions worked for me. I have an iPhone 7 and a mid 2015 MacBook pro. Everything is up to date as far as ios versions go. Today quite randomly I found that if I turn on the personal hotspot while the phone is plugged in the phone stops fluctuating between charging/not charging.

I have the same issue. I have an iPhoneX and a Macbook Air. Whenever I plug in my device just to charge it while I'm using my Mac, a prompt appears telling me to install an update on my iPhone X, when I click "Install" a pop up appears telling me the software is not available. Then it disconnects my iPhone and hence, no longer charging it. But with my old iPhone 5 I don't have an issue such as this one. I already messaged their tech support and provided screenshots but still no solution until now.

I finally figured out the solution to why my iphone kept charging off and on:

I had offloaded / deleted the Music (iTunes) app on my phone. After reinstalling this it allowed me to Trust the computer.

I did what welibelkov suggested:

1. Disconnect your iphone from cable.

2. On your iphone: ->Settings -> General -> Reset -> Reset Location & Privacy (accept all things).

3. Connect your iphone back to cable. (iphone will reconnecting again, don't worry, it will be soon over).

4. iTunes will ask about trust, accept all this.

But was unable to trust the computer cause my Music (itunes app wasnt installed)

For me it was the issue with the iPhone OS. So, I unplugged the USB from mac to phone and I plugged it into a wall socket and I updated my iPhone to the latest version and everything is fine now.. It might not be the same reason for everyone but for one who is running lower version in their mobiles might find this helpful...